- Step 3: Take the
measurement from step 1, choose
your clip-on. Note: If your
exact dimensions falls between
two different size clip-on, we
recommend that you pick the
larger of the two.

2. Take The number directly from
your glasses arm pieces

-
Step 1:

Most Prescription
Glasses frames have the size printed
on them usually on the inside of the
arm. If you have, or have access to
a pair of glasses which you feel
comfortable with, you can use these
sizes as a guide, i.e. 46-20-135.

The first number
represents the lens width, the
second number is the nose bridge
width (which is taken from half way
down the frame were the nose pads
are screwed to the frame), the
third number is the length of the
arm